Using Device Linking to Eavesdrop on WhatsApp and Signal
Modern messaging apps allow users to link their phone accounts to their computer desktop. Eavesdroppers are taking advantage of this capability:
> Apps such as WhatsApp Web and Signal Desktop allow people to use their accounts on other devices, such as laptops or desktop computers. > > Germany’s Customs Office has been using these features to connect a police-controlled computer to a suspect’s account. > > Once connected, messages can be delivered to that computer without the police having to crack the encryption protecting them. > > Netzpoltik details > that police are able to gain access in this way either through physical access to someone’s phone or by intercepting verification codes via a state-sanctioned phishing attack or intercepting SMS messages via telephone surveillance.
That last paragraph is important. Making this work requires user consent.
What we want is a feature that displays connected devices, so users could notice if a new device gets connected to their account.
Tags: eavesdropping , law enforcement , police , Signal , WhatsApp
Posted on September 29, 2026 at 7:02 AM • 26 Comments
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